Question on a pullover sweater pattern

my grandmas working on a patchwork pullover Front instructions say
work as for Back until 18(19,20,21,22,22)" from cast on edge or 3" less than back length. Bind off center 22 sts. Then, working both sides at the same time, bind off 4 sts at neck edge every other row 3 times. Continue on rem 27(29,32,35,37,40,43) sts until same length as back, bind off all sts.

her question is , how do i bind off 22 sts and the 4 sts at the same time?

thanks

You don’t bind them off at the same time. First work across one shoulder and BO the center stitches. Then finish the row. Turn and work the WS row, drop that yarn and use a new yarn end, BO 4 sts on the first shoulder and finish the row. Turn, and work to the neck, drop the yarn, pick up the yarn on the other side of the neck and BO 4 sts and finish the row. Keep working both shoulders separately, and BO at the beg of the rows until you have bound off 12 sts for each side, then BO the rest of the sts.

she understands , thank you very much